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I'm not sure what you're asking here. Fan-sites? CMS-based sites? CMS-like sites?
Slashdot I'm willing to bet has no problem beating those numbers. Bluesnews, Anandtech, Ars, Sourceforge all get a bazillion hits.
Some sites are sub-sites to a much larger network that all have something in common. There are of course the Warcry sites, Gamespy or the Vault network which each have a bazillion people on them all the time, all of which have computer games as their commonality for the sub-sites.